Summary: Immunizations

Spotlight on Key Indicators: Immunizations

Learn More About Immunizations

Health Care
Why This Topic Is Important
Immunizations are among the most successful and cost-effective preventive health care interventions, helping millions of children in the U.S. and internationally avoid contracting numerous serious and potentially fatal infectious diseases (1). Current immunization schedules recommend that children and adolescents should be immunized to protect against 16 diseases. These include: polio; diphtheria, tetanus, and whooping cough; measles, mumps, and rubella; chickenpox; hepatitis A and B; the flu; Haemophilus influenzae type b; pneumococcal and meningococcal diseases; rotavirus; and cervical cancer due to papillomavirus (2). Annual immunization against influenza also is recommended. Immunizations are important for the protection of the individual child as well as for the protection of others with whom an infected child might come in contact; all of these diseases are contagious and most are spread through air or direct contact (3). For each U.S. birth cohort that is vaccinated in a timely manner, it is estimated that 33,000 lives are saved, nationwide, and that direct health care costs to society are reduced by $9.9 billion (1).

While the data on reflect the number and percentage of kindergarteners who received all required immunizations by the time they started school, a child is considered to have been fully immunized on time only if all immunizations were received by age 3 (4).
For more information on immunizations, please see’s Research & Links Section.

Sources for this narrative:

1.  Healthy People 2020. (n.d.). Immunizations and infectious diseases. Retrieved from:

2.  Centers for Disease Control and Prevention. (2015). Parent’s guide to childhood immunizations. Retrieved from:

3.  Centers for Disease Control and Prevention. (2016). 2016 recommended immunizations for children from birth through 6 years old. Retrieved from:

4.  Elam-Evans, L. D., et al. (2014). National, state, and local area vaccination coverage among children aged 19-35 months—United States, 2013. Morbidity and Mortality Weekly Report, 63(34), 741-748. Retrieved from:
How Children Are Faring
The California School Immunization Law requires that children receive certain immunizations before entering school. In 2016, 93% of California kindergartners received all state-required immunizations by the time they entered school, a slight increase in comparison to recent years. Among counties with available data in 2016, percentages ranged from 77% to 100%.

Some students are exempt from the immunization requirements. In 2016, 2.4% of California kindergartners were exempt due to their parents' personal beliefs, 0.2% were exempt for medical conditions, and 4.4% were exempt for other reasons. An additional 0.2% were overdue for one or more immunizations. The percentage of children with personal belief exemptions in 2016 ranged widely at the county level, from less than 1% to more than 18%, among counties with available data.

In 2014, the number of cases of pertussis (whooping cough), a highly contagious and potentially life-threatening disease that is vaccine-preventable, peaked in California. That year, 11,213 cases of pertussis were diagnosed, accounting for 34% of all of the cases diagnosed in the U.S. California's 2014 pertussis rate, 29 per 100,000 people, was almost three times the rate nationwide (10.3). There was striking variation at the county level, with rates per 100,000 ranging from 0.0 to more than 100.0 in some Northern California counties. Pertussis accounts for the majority of all vaccine-preventable diseases diagnosed.
Policy Implications
State policy currently requires proof of recommended immunizations as a condition of entry into kindergarten, preschool, and licensed child care, which means that immunization rates are relatively high for children entering those settings (1). Overall, however, infants and toddlers have lower vaccination rates than school-age children, making them particularly vulnerable to communicable diseases (2). State policy can improve immunization rates by helping to ensure that children see a doctor, parents understand the importance of timely vaccinations, and affordable and accessible vaccination resources are available. Progress has been made in this regard; recently, the Affordable Care Act mandated that private health plans fully cover the costs of all recommended vaccinations. However, issues of access and education persist (3, 4, 5). According to research and subject experts, policy options that could improve immunization rates include:
  • Exploring additional options for reaching adolescents, who frequently fail to complete the recommended courses of vaccinations (3)
  • Ensuring more universal use of immunization registry systems, which are confidential, computerized systems that contain children's vaccination histories within a geographic area, and advancing communication among registries (4)
  • Providing affordable health insurance coverage to all children that reduces the out-of-pocket costs of immunizations (3), and ensuring that children have a “medical home” (5, 6)
  • Supporting public education about the importance of timely immunization, along with other interventions, such as reminder systems (4, 5, 7) and creating educational materials that are easy to understand and culturally appropriate (7)
  • Minimizing barriers that restrict access to vaccinations, such as cost, clinic accessibility, and vaccine availability (7)
  • Equipping pediatricians and other health care advisors with the tools to address the concerns of vaccine-hesitant parents (8)
  • Assessing the process and availability of non-medical exemptions for opting out of immunizations, as exemption rates are up nationwide and are highest in states that have easy exemptions procedures and allow for nonmedical exemptions, such as California (9)
  • Exploring strategies to increase the HPV vaccination rate among teens by administering it during the same visit as other vaccines and educating parents and youth as to its importance (3, 10).
For more policy ideas about immunizations, visit's Research & Links section on this page, the California Immunization Coalition, or Shots for School. Also see Policy Implications under our Health Care topic.

Sources for this narrative:

1.  California Department of Public Health, Immunization Branch. (2015). 2014-2015 child care and school fact sheet. Retrieved from:

2.  Salmon, D. A., et al. (2006). Measuring immunization coverage among preschool children: Past, present, and future opportunities. Epidemiologic Reviews, 28(1), 27-40. Retrieved from:

3.  Elam-Evans, L. D., et al. (2014). National, state, and local area vaccination coverage among children aged 19-35 months—United States, 2013. Morbidity and Mortality Weekly Report, 63(34), 741-748. Retrieved from:

4.  Centers for Disease Control and Prevention. (2011). General recommendations on immunization: Recommendations of the Advisory Committee on Immunization Practices (ACIP). Morbidity and Mortality Weekly Report, 60(RR-2), 1-60. Retrieved from:

5.  American Academy of Pediatrics. (2013). Adolescent immunizations: Strategies for increasing coverage rates. Retrieved from:

6.  Allred, N. J., et al. (2007). The association of health insurance and continuous primary care in the medical home on vaccination coverage for 19- to 35-month-old children. Pediatrics, 119(Suppl. 1), S4-S11. Retrieved from:

7.  Kimmel, S. R., et al. (2007). Addressing immunization barriers, benefits, and risks. Journal of Family Practice, 56(2), S61-S69. Retrieved from:

8.  American Academy of Pediatrics. (2013). Addressing common concerns of vaccine-hesitant parents. Retrieved from:

9.  Omer, S. B., et al. (2012). Vaccination policies and rates of exemption from immunization, 2005-2011. New England Journal of Medicine, 367(12), 1170-1171. Retrieved from:

10.  Centers for Disease Control and Prevention. (2013). Human papillomavirus vaccination coverage among adolescent girls, 2007-2012, and postlicensure vaccine safety monitoring, 2006-2013—United States. Morbidity and Mortality Weekly Report, 62(29), 591-595. Retrieved from:
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